The rapid growth of 3G/4G enabled devices such as smartphones and tablets in large numbers has created increased demand for mobile data services. Wi-Fi offloading helps satisfy the requirements of data-rich applicatio...The rapid growth of 3G/4G enabled devices such as smartphones and tablets in large numbers has created increased demand for mobile data services. Wi-Fi offloading helps satisfy the requirements of data-rich applications and terminals with improved multi- media. Wi-Fi is an essential approach to alleviating mobile data traffic load on a cellular network because it provides extra capacity and improves overall performance. In this paper, we propose an integrated LTE/Wi-Fi architecture with software-defined networking （SDN） abstraction in mobile baekhaul and enhanced components that facilitate the move towards next-generation 5G mo- bile networks. Our proposed architecture enables programmable offloading policies that take into account real-time network conditions as well as the status of devices and applications. This mechanism improves overall network performance by deriving real- time policies and steering traffic between cellular and Wi-Fi networks more efficiently.展开更多
信息物理融合电力系统连锁故障中,信息层延时对故障的发展起到推波助澜的作用。为了降低系统故障风险,有必要在故障环境下分析降低延时的方法及其影响。为了缓解信息层信息传输延时和拥塞,首先将软件定义网络（soft defined networks,SD...信息物理融合电力系统连锁故障中,信息层延时对故障的发展起到推波助澜的作用。为了降低系统故障风险,有必要在故障环境下分析降低延时的方法及其影响。为了缓解信息层信息传输延时和拥塞,首先将软件定义网络（soft defined networks,SDN）的构架引入信息物理融合电力系统信息层,提出基于SDN的信息层动态优化路由策略。进而对比了小世界信息层网络和无标度信息层网络下,采用静态路由策略和SDN动态优化路由策略时的传输延时和节点拥堵情况。最后,回到信息物理融合电力系统连锁故障模拟场景,对比讨论了两种路由策略对不同规模连锁故障发展的影响。在小世界信息层网络和无标度信息层网络中,采用SDN动态优化路由策略平衡了不同节点的排队压力,缓解了拥堵程度,降低了最长信息传输延时和平均信息传输延时。连锁故障模拟表明,信息层动态优化路由策略提高了故障中物理电网安全控制的准确性且降低了连锁故障风险。展开更多
针对数据中心网络(data center network,DCN)动态调度导致的负载不均衡问题,提出了基于流调度选择的动态负载均衡(dynamic load balancing based on flow scheduling selection,DLBFSS)算法。该算法首先计算拥塞链路上各条大流的等价最...针对数据中心网络(data center network,DCN)动态调度导致的负载不均衡问题,提出了基于流调度选择的动态负载均衡(dynamic load balancing based on flow scheduling selection,DLBFSS)算法。该算法首先计算拥塞链路上各条大流的等价最短路径,并删除不满足流带宽需求的路径;然后计算剩余路径的可用吞吐量,选择可用吞吐量最大的路径作为最优调度路径;最后根据大流的带宽和最优路径的负载定义调度的拥塞概率,将拥塞概率作为大流调度选择的依据。实验结果表明,与传统ECMP(equal-cost multi-path)路由和现有大流调度算法相比,DLBFSS能够减小网络时延,提高流的带宽利用率,保证了更好的负载均衡。展开更多
文摘The rapid growth of 3G/4G enabled devices such as smartphones and tablets in large numbers has created increased demand for mobile data services. Wi-Fi offloading helps satisfy the requirements of data-rich applications and terminals with improved multi- media. Wi-Fi is an essential approach to alleviating mobile data traffic load on a cellular network because it provides extra capacity and improves overall performance. In this paper, we propose an integrated LTE/Wi-Fi architecture with software-defined networking （SDN） abstraction in mobile baekhaul and enhanced components that facilitate the move towards next-generation 5G mo- bile networks. Our proposed architecture enables programmable offloading policies that take into account real-time network conditions as well as the status of devices and applications. This mechanism improves overall network performance by deriving real- time policies and steering traffic between cellular and Wi-Fi networks more efficiently.
文摘信息物理融合电力系统连锁故障中,信息层延时对故障的发展起到推波助澜的作用。为了降低系统故障风险,有必要在故障环境下分析降低延时的方法及其影响。为了缓解信息层信息传输延时和拥塞,首先将软件定义网络（soft defined networks,SDN）的构架引入信息物理融合电力系统信息层,提出基于SDN的信息层动态优化路由策略。进而对比了小世界信息层网络和无标度信息层网络下,采用静态路由策略和SDN动态优化路由策略时的传输延时和节点拥堵情况。最后,回到信息物理融合电力系统连锁故障模拟场景,对比讨论了两种路由策略对不同规模连锁故障发展的影响。在小世界信息层网络和无标度信息层网络中,采用SDN动态优化路由策略平衡了不同节点的排队压力,缓解了拥堵程度,降低了最长信息传输延时和平均信息传输延时。连锁故障模拟表明,信息层动态优化路由策略提高了故障中物理电网安全控制的准确性且降低了连锁故障风险。
文摘针对数据中心网络(data center network,DCN)动态调度导致的负载不均衡问题,提出了基于流调度选择的动态负载均衡(dynamic load balancing based on flow scheduling selection,DLBFSS)算法。该算法首先计算拥塞链路上各条大流的等价最短路径,并删除不满足流带宽需求的路径;然后计算剩余路径的可用吞吐量,选择可用吞吐量最大的路径作为最优调度路径;最后根据大流的带宽和最优路径的负载定义调度的拥塞概率,将拥塞概率作为大流调度选择的依据。实验结果表明,与传统ECMP(equal-cost multi-path)路由和现有大流调度算法相比,DLBFSS能够减小网络时延,提高流的带宽利用率,保证了更好的负载均衡。
